title: Who is at risk of long hospital stay among patients admitted to geriatric acute care unit? Results from a prospective cohort study.
abstract: OBJECTIVE
  (1) To confirm that vitamin D deficiency, defined as serum 25-hydroxyvitamin D (25OHD) concentration < 25 nmol/L, was associated with long length-of-stay (LOS) among older inpatients admitted to geriatric acute care unit; and (2) to examine which combination of risk factors of longer LOS including vitamin D deficiency best predicted longer LOS.
  
  
  METHODS
  Based on a prospective cohort study with a 25-day follow-up on average, 531 consecutive older inpatients (mean age 85.0±7.2 years, 59.1% women) admitted to the geriatric acute care unit of Angers University Hospital, France, were included.
  
  
  RESULTS
  Linear regression models showed that male gender (P<0.025), delirium (P<0.015) and vitamin D deficiency (P<0.001) were independently associated with a longer LOS. The highest risk of a longer LOS was shown while combining vitamin D deficiency with male gender (Odds ratio (OR)=3.70 with P< 0.001). The risk increased significantly while delirium was associated with these two baseline characteristics (OR=4.76 with P=0.001). Kaplan-Meier distributions of discharge differed significantly between participants who had or not the combination of the 3 criteria (P<0.007).
  
  
  CONCLUSIONS
  Vitamin D deficiency, delirium and male gender were significant risk factors for a longer LOS in the studied sample of older inpatients.
authors.affiliation: Olivier Beauchet, MD, PhD, Department of Neuroscience, Division of Geriatric Medicine, Angers University Hospital, Angers, France; 49933 Angers Cedex 9, France; E-mail: olbeauchet@chu-angers.fr; Phone: ++33 2 41 35 47 25; Fax: ++33 2 41 35 48 94.
authors.forename: O
authors.initials: O
authors.lastname: Beauchet
authors.forename: C
authors.initials: C
authors.lastname: Launay
authors.forename: L
authors.initials: L
authors.lastname: de Decker
authors.forename: B
authors.initials: B
authors.lastname: Fantino
authors.forename: A
authors.initials: A
authors.lastname: Kabeshova
authors.forename: C
authors.initials: C
authors.lastname: Annweiler
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003422:Critical Care; D003693:Delirium / Q000150:complications; D005260:Female; D005602:France; D005853:Geriatrics; D006757:Hospital Units; D006801:Humans; D053208:Kaplan-Meier Estimate; D007902:Length of Stay; D016014:Linear Models; D008297:Male; D016017:Odds Ratio; D011446:Prospective Studies; D012307:Risk Factors; D012737:Sex Factors; D014808:Vitamin D Deficiency / Q000097:blood / Q000150:complications